THEMIS Particle Moments (Ground): Difference between revisions

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m (Floresaa moved page THEMIS Particle Moments to THEMIS Particle Moments (Ground) without leaving a redirect: differentiate between ground and spacecraft processed moments)
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[[File:peef_moments_example.png|200px|thumb|right|Density, velocity, and temperature for ESA electrons.]]
[[File:peef_moments_example.png|200px|thumb|right|Density, velocity, and temperature for ESA electrons.]]


A variety of data products can be derived by computing the moments of measured THEMIS particle data.  Moments are produced after selecting a spacecraft, particle data type, and time range.  Some products also require a magnetic field variable.
Moments of the particle distribution may be calculated manually.  This allows for manual calibration and specification of input parameters.  Moments may be produced after selecting a spacecraft, particle data type, and time range.  Some products also require magnetic field data to be present.


For command line usage see:
For command line usage see:
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==Products==
For spacecraft processed moments see [[THEMIS Particle Moments (Spacecraft)|on-board moments]].
Products marked with a * require magnetic field data to be loaded. All "vector" data types are 3-vectors.  Symmetric tensors are stored in six dimensions: xx, yy, zz, xy, xz, yz.
 
 
==Overview==
All data products are calculated simultaneously for a particular data type.  "Moments" must be specified in the outputs.
 
<div style="border: 1px solid LightGray; background-color:#F9F9F9; padding: 2px 10px; margin-left: 5px; overflow:hidden">
SPEDAS>  thm_part_products, probe='a', datatype='peif', trange=[t0,t1], '''outputs = 'moments' '''
</div>
 
Support data will be used automatically if it is present.  By default the software will use "th?_fgs" as the magnetic field and "th?_pxxm_pot" as the spacecraft potential ("?" denoting probe designation).  If no support data is found it will quietly be ignored and any derived quantities will note be calculated.  Keywords may be used to specify support data:
 
<div style="border: 1px solid LightGray; background-color:#F9F9F9; padding: 2px 10px; margin-left: 5px; overflow:hidden">
SPEDAS>  thm_part_products, probe='a', datatype='peif', trange=[t0,t1], outputs = 'moments', '''mag_name='tha_fgl', sc_pot_name='tha_peef_sc_pot' '''
</div>
 
====Data Products====
Products marked with a * require magnetic field data to be loaded.
 
All "vector" data types are 3-vectors.  Symmetric tensors are stored in six dimensions: xx, yy, zz, xy, xz, yz.


{| class="wikitable" style="border: 1px solid LightGray; background-color:#F9F9F9; margin-left:5px;"
{| class="wikitable" style="border: 1px solid LightGray; background-color:#F9F9F9; margin-left:5px;"

Revision as of 23:05, 9 March 2015

Density, velocity, and temperature for ESA electrons.

Moments of the particle distribution may be calculated manually. This allows for manual calibration and specification of input parameters. Moments may be produced after selecting a spacecraft, particle data type, and time range. Some products also require magnetic field data to be present.

For command line usage see:

/projects/THEMIS/examples/basic/thm_crib_part_products.pro


For spacecraft processed moments see on-board moments.


Overview

All data products are calculated simultaneously for a particular data type. "Moments" must be specified in the outputs.

SPEDAS> thm_part_products, probe='a', datatype='peif', trange=[t0,t1], outputs = 'moments'

Support data will be used automatically if it is present. By default the software will use "th?_fgs" as the magnetic field and "th?_pxxm_pot" as the spacecraft potential ("?" denoting probe designation). If no support data is found it will quietly be ignored and any derived quantities will note be calculated. Keywords may be used to specify support data:

SPEDAS> thm_part_products, probe='a', datatype='peif', trange=[t0,t1], outputs = 'moments', mag_name='tha_fgl', sc_pot_name='tha_peef_sc_pot'

Data Products

Products marked with a * require magnetic field data to be loaded.

All "vector" data types are 3-vectors. Symmetric tensors are stored in six dimensions: xx, yy, zz, xy, xz, yz.

Variable Name Description Units Data type
density Density 1/cm3 scalar
current Current scalar
flux Number flux 1/(s·cm2) vector
eflux Energy flux eV/(s·cm2) vector
velocity Velocity km/s vector
t3 Diagonalized temperature eV vector
magt3 Magnetic field aligned temperature* eV vector
avgtemp Average temperature eV scalar
vthermal Thermal velocity km/s vector
mftens Momentum flux tensor eV/cm3 symmetric tensor
ptens Pressure tensor eV/cm3 symmetric tensor
symm Direction of pressure tensor symmetry n/a vector
symm_phi Phi (longitude) direction of symmetry vector ° scalar
symm_theta Theta (latitude) direction of symmetry vector ° scalar
symm_ang Angle between symmetry vector and magnetic field* ° scalar

Contamination

Uncertainty estimates

Resources

ESA instrument page

SST instrument page